This invention relates to apparatus for welding tubes to a tubesheet of a heat exchanger and more particularly to such an apparatus utilizing a continuous weld to weld a portion of a row of tubes to a tubesheet.
When welding tubes to a tubesheet, initiating and extinguishing the arc as each tube is welded to the tubesheet requires a considerable portion of the total welding time, and also during the initiation and extinguishing of the arc the quality of the weld is likely to be lower than during other portions of the weld.